Methinks they’re not looking.
If they really wanted to know....they would check the blood work of 1% of the vaccinated 2 weeks after vaccination to look for biochemical signature of cardiac issues. But I think they believe it is so low that any event can be explained away by “ unknown” factors...
My bunch is that there is a bit of cardiac damage but too small to cause any clinical symptoms. I cannot back up the hunch with science, except with the old adage, “where there’s smoke, there is fire”.